1. Field of the Invention
The present invention relates to poly(vinyliminomethylene) polymers. This invention also relates to vinyl isocyanide compounds for the preparation thereof.
2. Description of the Prior Art:
The homopolymerization of isocyanides, RNC, yields a rather unusual class of polymers, namely the poly(iminomethylenes), having the formula [R--N.dbd.C&lt;].sub.n. These polymers are of interest as their viscosity behavior, Debye-Scherrer X-ray composites, and optical rotation data suggest that the polymers have a rigid rod helical structure. The same structure appears to be consistent with observations from molecular models. F. Millich, Adv. Polym. Sci., 19, 117 (1975) and Chem. Rev., 72, 101 (1972). With the recognition that a helical structure is the most likely structure, subsequent experimentation soon indicated that various isocyanide oligomers could be resolved into fractions having (+) and (-) signs of optical rotation. R. J. M. Nolte et al, J. Am. Chem. Soc. 96, 5932 (1974). Hence, the poly(iminomethylenes) appear to have a chiral helical rigid rod structure.
While various metals have been tested as catalysts for the isocyanide homopolymerization reaction, nickel (II) compounds have emerged as the catalysts of choice for the preparation of poly(iminomethylenes).
The first characterized high polymer of an isocyanide, RNC, and a catalytic synthetic procedure were reported in 1965. However, although some polyisocyanide studies have been conducted, as described above, more extensive investigations of the synthesis and properties of these polymers have been hampered by the extreme insolubility of most of the poly(iminomethylenes). Morever, the polymer insolubilities have largely prevented investigations pertaining to the possible uses for these polymers. With the combination of chirality and rigidity, the poly(iminomethylenes) should offer a wide range of uses such as selective supports in chromatography, as enantioselective catalysts, and as specific reagents with respect to substrates of biochemical importance. Unfortunately, the realization of these possibilities has been frustrated due to the insolubility of the poly(iminomethylenes).
Therefore, a need clearly exists either for a poly(iminomethylene) type polymer which has a dramatically improved solubility or for a closely related soluble polymer which would facilitate the additional study and use of these polymers as described above.